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How to Face Mill
Guide · Updated October 28, 2026
Face milling cuts the top of a part flat and to thickness with a multi-insert cutter. It's often the first and last operation on a block, so flatness, finish and size all depend on it.
Hit your thickness
Check thickness with a mic you've verified against gage blocks; the free Gage Block Calculator builds the stack.
Step by step
- Hold it flat: Seat the part on parallels in a trued vise and tap it down.
- Pick the cutter: Choose a face mill about 1.3–1.6× the width of cut so the cutter overhangs the part.
- Set speeds and feeds: Use the insert maker's surface speed and chip load per tooth.
- Plan the path: Enter with the cutter in a climb position and keep about 2/3 of the cutter engaged.
- Rough: Take roughing passes, leaving about 0.010–0.020 in.
- Finish: Take a single finish pass at full width if possible to avoid steps between passes.
- Measure: Measure thickness in several places and deburr.
Worked example
3 in wide part, 4 in face mill with 5 inserts, aluminum at 1500 SFM: RPM = 1500 × 3.82 / 4 ≈ 1430. At 0.006 in per tooth, feed = 1430 × 5 × 0.006 ≈ 43 in/min.
Steps between passes
A step usually means the spindle is out of tram or the part moved. Tram the head, or finish in one pass wider than the part.
Face mill vs fly cutter
A face mill removes metal quickly with many inserts. A fly cutter is slower but gives a fine finish on small machines.
Tips
- Tram first; see tramming a mill.
- True the vise: indicating a vise.
- Use milling speeds and feeds.
- Check parallelism with this guide.
FAQ
What size face mill should I use?
Roughly 1.3 to 1.6 times the width of cut so the cutter overhangs both edges.
Why does my face mill leave steps?
The head is usually out of tram or the part shifted; finishing in one pass also helps.
Should I climb or conventional face mill?
Climb milling generally gives better finish and tool life on rigid machines.
How much should I leave for a finish pass?
About 0.010 to 0.020 in is common.
Can I face mill on a small benchtop mill?
Yes, with a smaller cutter and lighter cuts, or use a fly cutter for finish.
Related guides and calculators
- How to Use a Fly Cutter
- Milling Speeds and Feeds
- How to Tram a Mill
- How to Indicate a Vise True
- Parallels and Setup Blocks Basics
- Flatness and Parallelism Checks with Gage Blocks
- Surface Finish Basics
- How to Read an Inch Micrometer
- How to Use a Ball End Mill
- How to Use a Slitting Saw
- How to Face on a Lathe
- Chamfer Mill Basics
- How to Set Up a Milling Vise
- How to Use Parallels in a Vise
- Leadscrew Backlash Basics
- Cast Iron Speeds and Feeds
- How to Use a Vertical Milling Attachment
- All free machinist calculators
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